| A | B |
|---|
| element | a substance that can't be broken down into other substances by heat, light, or electricity. |
| periodic table | a chart that classifies elements by their properties. |
| atom | the smallest particle of an element that has the properties of the element. |
| nucleus | the cell part that controls the cell's activities; the center of an atom, where protons and neutrons are located. |
| proton | particle in an atom that has a positive charge. |
| neutron | a particle in an atom that has no charge. |
| electron | a particle in an atom that has a negative electrical charge. |
| molecule | two or more atoms joined together; the smallest unit of many substances. |
| compound | a substance made up of atoms of more than one element. |
| mixture | two or more substances that are mixed together, but can be separated out because teir atoms are not combined. |
| solution | a mixture which a substance breaks up into its most basic particles, which are too small to be seen, and spreads evenly through another aubstance. |
| physical property | a way of describing an object using traits that can be observed or measured without changing the substance into something else. |
| physcical change | a change in one or more physical properties. |
| chemical change | a change that produces new substance with new properties. |
| chemical reaction | a process that produces one or more substances that are different from the original substances. |
| chemical property | describes the way a substance reacts with other substances. |
